Android™ Application Development - Bahar Ali Khan

es/anim/popin.xml
Chapter 11: Advanced Android Development
res/anim/popinlayout.xml
Using Layout Animations
Once you’ve defi ned a Layout Animation, you can apply it to a ViewGroup either in code or in the layout
XML resource. In XML this is done using the android:layoutAnimation tag in the layout defi nition,
as shown in the following XML snippet:
android:layoutAnimation=”@anim/popinlayout”
To set a Layout Animation in code, call setLayoutAnimation on the View Group, passing in a reference
to the LayoutAnimation object you want to apply.
In both cases, the Layout Animation will execute once, when the View Group is fi rst laid out. You can
force it to execute again by calling scheduleLayoutAnimation on the ViewGroup object. The animation
will be executed the next time the View Group is laid out.
Layout Animations also support Animation Listeners.
In the following code snippet, a ViewGroup’s animation is re-run with a listener attached to trigger
additional actions once it’s complete:
aViewGroup.setLayoutAnimationListener(new AnimationListener() {
public void onAnimationEnd(Animation _animation) {
// TODO: Actions on animation complete.
}
public void onAnimationRepeat(Animation _animation) {}
public void onAnimationStart(Animation _animation) {}
});
aViewGroup.scheduleLayoutAnimation();
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